Showing papers by "Mohsen Guizani published in 2012"

A novel ID-based authentication framework with adaptive privacy preservation for VANETs

Abstract: In Vehicular Ad hoc Networks (VANETs), authentication is a crucial security requirement to avoid attacks to both inter-vehicle and vehicle-roadside communication. Vehicles have to be prevented from the misuse of their private data and the attacks on their privacy. In this paper, we investigate the authentication and privacy issues in VANETs. We propose a novel ID-based authentication framework with adaptive privacy preservation for VANETs. In this framework, adaptive self-generated pseudonyms are used as identifiers instead of real-world IDs. The update of the pseudonyms depends on vehicular demands. The ID-Based Signature (IBS) scheme and the ID-Based Online/Offline Signature (IBOOS) scheme are used, for authentication between the Road Side Units (RSUs) and vehicles, as well as authentication among vehicles, respectively. System evaluation has been executed using efficient IBS and IBOOS schemes. It shows that, the proposed authentication framework with privacy preservation is suitable to the VANET environment.

Secure service provision in smart grid communications

Abstract: The smart grid provides a platform for thirdparty service providers to remotely monitor and manage energy usage for consumers. At the same time, the involvement of service providers brings a new set of security threats to the smart grid. In this article, we first identify the cyber security challenges on service provision in the smart grid. Then we present two main security issues related to service provision and provide potential solutions. The first one is to establish a secure communication procedure among the electric utility, consumers, and service providers. The second one is to provide a privacy-preserving yet accountable authentication framework among the smart grid entities without relying on any trusted third party. Finally, we suggest directions of future work on secure service provision by describing several open issues.

Secondary users cooperation in cognitive radio networks: balancing sensing accuracy and efficiency

Abstract: Cooperative spectrum sensing is a promising technique in cognitive radio networks by exploiting multi-user diversity to mitigate channel fading. Cooperative sensing is traditionally employed to improve the sensing accuracy while the sensing efficiency has been largely ignored. However, both sensing accuracy and efficiency have very significant impacts on the overall system performance. In this article, we first identify the fundamental trade-off between sensing accuracy and efficiency in spectrum sensing in cognitive radio networks. Then, we present several different cooperation mechanisms, including sequential, full-parallel, semi-parallel, synchronous, and asynchronous cooperative sensing schemes. The proposed cooperation mechanisms and the sensing accuracy-efficiency trade-off in these schemes are elaborated and analyzed with respect to a new performance metric achievable throughput, which simultaneously considers both transmission gain and sensing overhead. Illustrative results indicate that parallel and asynchronous cooperation strategies are able to achieve much higher performance, compared to existing and traditional cooperative spectrum sensing in cognitive radio networks.

PKC Based Broadcast Authentication using Signature Amortization for WSNs

Abstract: Public Key Cryptography (PKC) is widely used for broadcast authentication. Intensive use of PKC for broadcast authentication, however, is thought to be expensive to resource constrained sensor nodes. In this paper, we propose a novel PKC based broadcast authentication scheme using signature amortization for Wireless Sensor Networks (WSNs). The proposed scheme exploits only one Elliptic Curve Digital Signature Algorithm (ECDSA) signature to authenticate all broadcast messages. Thus, the overhead for the signature is amortized over all broadcast messages. Besides low overhead, the proposed scheme retains high security that is as strong as conventional PKC based broadcast authentication schemes. Moreover, the proposed scheme can achieve immediate authentication and does not require time synchronization. For the implementation of the proposed scheme, an efficient public key distribution protocol is also presented in this paper. Experimental results of a testbed show that the overhead for authenticating a broadcast message is reduced significantly.

Radio and Medium Access Contention Aware Routing for Lifetime Maximization in Multichannel Sensor Networks

Abstract: In this paper, we develop cross-layer techniques suitable for wireless sensor networks (WSNs) that are capable of multichannel access. More specifically, we propose energy and cross-layer aware routing schemes for multichannel access WSNs that account for radio, MAC contention, and network constraints. By doing so, we guarantee to meet data rate requirements of end-to-end flows while maximizing the network lifetime. When MAC contention constraints associated with the shared wireless medium are not included in routing formulations, routing solutions may not be feasible, in that the shared medium may not be able to support the required data rates of these flows. In this paper, we first derive three sets of sufficient conditions that ensure feasibility of data rates in multichannel access WSNs. Then, utilizing these sets, we devise three different MAC-aware routing optimization schemes, each aiming to maximize the network lifetime. Finally, we perform extensive simulation studies to evaluate and compare the performance of the proposed routing approaches under various network conditions.

A lightweight privacy-preserving protocol using chameleon hashing for secure vehicular communications

Abstract: Many services and applications in vehicular ad-hoc networks (VANETs) require preserving and secure data communications. To improve driving safety and comfort, the traffic-related status information will be broadcasted regularly and shared among drivers. Without the security and privacy guarantee, attackers could track their interested vehicles by collecting and analyzing their traffic messages. Hence, anonymous message authentication is an essential requirement of VANETs. On the other hand, when a vehicle is involved in a dispute event of warning message, the certificate authority should be able to recover the real identity of this vehicle. To deal with this issue, we propose a new privacy-preserving authentication protocol with authority traceability using elliptic curve based chameleon hashing. Compared with existing schemes, our approach possesses the following features: (1) mutual and anonymous authentication, (2) unlinkability, (3) authority tracking capability and (4) high efficiency. We also demonstrate the merits of our proposed scheme through extensive security analysis and performance evaluation.

Discovering influential users in micro-blog marketing with influence maximization mechanism

Abstract: Micro-blog marketing has become a main business model for social networks nowadays. On social networking sites (e.g., Twitter), micro-blog marketing enables the advertisers to put ads to attract customers to buy their products. During this process, a rather key step for the success of advertisers is to conduct marketing researches to discover which micro-blog users are their potential customers who can greatly promote their products to other customers so that the advertising investment can be greatly reduced. This problem is considered as “influence maximization” issue. In this paper and in attempt to discover the influential users in micro-blog marketing, we try to analyze the influences of nodes in a micro-blog network and propose a Community Scale-Sensitive Maxdegree (CSSM) algorithm for maximizing the influences when placing ads. Experimental results on the very hot micro-blog service (i.e., Twitter dataset) demonstrate that our proposed CSSM algorithm significantly outperforms other related node selection strategies, in terms of the influence spread and time complexity.

NCAC-MAC: Network coding aware cooperative medium access control for wireless networks

Abstract: Cooperative communication, which utilizes neighboring nodes to relay the overhearing information, has been employed as an effective technique to deal with the channel fading and to improve the network performances. And network coding, which combines several packets together for transmission, is very helpful to reduce the redundancy at the network and to increase the overall throughput. Introducing network coding into the cooperative retransmission process, enables the relay node to assist other nodes while serving its own traffic simultaneously. To leverage the benefits brought by both of them, an efficient Medium Access Control (MAC) protocol is needed. In this paper, we propose a novel network coding aware cooperative MAC protocol, namely NCAC-MAC, for wireless networks. The design objective of NCAC-MAC is to increase the throughput and reduce the delay of the network. Simulation results reveal that our NCAC-MAC can improve the network performance under general circumstances.

Lightweight secure global time synchronization for Wireless Sensor Networks

Abstract: Time synchronization is crucial to Wireless Sensor Networks (WSNs) due to the requirement of coordination between sensor nodes. Existing secure time synchronization protocols of WSNs introduce high overhead when used for global time synchronization. In this paper, we propose a lightweight secure global time synchronization protocol for WSNs. In the proposed protocol, a broadcast synchronization packet makes all sensor nodes in the network synchronize with the trusted source. The synchronization packet is protected by a proposed broadcast authentication algorithm, which introduces asymmetry by transmitting hash values of secret keys in advance. It achieves immediate authentication and does not require the loose time synchronization. To defend the pulse-delay attacks, the arrival time of the synchronization packet is checked according to the estimated arrival time interval. The upper bound on the skew of the proposed protocol is proved. The message complexity in one period of the proposed protocol is O(n) where n represents the number of sensor nodes. The simulation results show that the maximum skew is within tens of milliseconds.

Cognitive transmission based on data priority classification in WSNs for Smart Grid

Abstract: Smart Grid integrates digital processing, sensor technology, automatic control and communication to the traditional power grid to achieve more efficient electricity distribution and management. Applying wireless sensor networks (WSNs) to Smart Grid can greatly facilitate the real-time information exchange within the power management system, and enable fast adaptation of the system to environmental changes. However, there are many challenges that need to be addressed for applying WSNs to the Smart Grid. One critical issue is how to receive data at the controller's node in a timely manner considering the typically time sensitive environment in Smart Grid and the limited battery power supply in WSNs. Based on data classification, this paper proposes a data transmission strategy in WSNs. After appropriate processing while collecting those large and complex data during aggregation, they are classified into different priority levels according to their various features. This classification process ensures the most important data which occupy a quite small percent of the total amount. The proposed cognitive transmission measure can guarantee a minimum delay for the most key data under the constraints of the electric-power-system environment and battery power supply. We offer simulation results to show the performance of the proposed cognitive transmission scheme.

EM-Based Adaptive Frequency Domain Estimation of Doppler Shifts with CRLB Analysis for CDMA Systems

Abstract: Combating time and frequency selectivity in wireless channels is one of the most challenging tasks in next generation wireless networks. In this paper, we propose an adaptive estimation algorithm to estimate Doppler shifts in a direct sequence code division multiple access (DS-CDMA) radio system with multiple Doppler subpaths. By modeling doubly selective channels using a basis expansion model (BEM), an expectation-maximization (EM) algorithm based adaptive estimation method is developed to extract accurate Doppler shift information. The Cramer-Rao lower bound (CRLB) analysis is conducted to study the performance bound of the proposed estimation algorithm. Based on the estimated Doppler shift results, a frequency domain equalizer (FDE) based receiver architecture is developed to exploit Doppler diversity in the frequency domain. Our analysis and simulation results demonstrate that this receiver architecture features a low complexity while still achieving a good performance compared with traditional CDMA receivers.

How Mobility Impacts Video Streaming over Multi-Hop Wireless Networks?

Abstract: In this work, we investigate the impact of mobility on video streaming over multi-hop wireless networks by utilizing a class of scheduling schemes We show that node spatial mobility has the ability to improve video quality and reduce the transmission delay without the help of advanced video coding techniques To describe a practical mobile scenario, we consider a random walk mobility model in which each node can randomly and independently choose its mobility direction, and all the nodes can identically and uniformly visit the entire network The contributions of this work are twofold: 1) It studies the optimal node velocity for the mobile video system In this case, it is possible to achieve almost constant transmission delay and video quality as the number of nodes increases; 2) It derives an achievable quality-delay tradeoff range for different node velocities Therefore, it is helpful to shed insights on network design and fundamental guidelines on establishing an efficient mobile video transmission system

Dynamic cluster based price control and gateway management for VANETs

Abstract: With the increasing demand of communication, it is of great necessity to maximize the utility of vehicular network VANETs (Vehicular Ad-hoc Networks) especially in the context of high mobility attract more attention all over the world Pure vehicle-to-vehicle(V2V) networks may relatively have long delay and worse performance compared to vehicle-to-infrastructure(V2I) networks, while V2V networks have larger communication area Consequently, vehicular network integrated with 3G network is of significance In these networks, gateways are generally used as interfaces between hybrid networks, thus gateway selection becomes the primary challenge The most important thing considered in our work is that whenever infrastructures and 3G networks are considered, price is a core problem The justice of caring the interests of all the vehicle nodes is going to be considered In this paper, we consider the VANET and 3G connected model under cognitive situations, and then a price based on hierarchical strategy on the cooperative sensing and cluster head selection is proposed to ensure the maximum benefit of both the cluster heads and the cluster members

Maximizing Secondary-User Satisfaction in Large-Scale DSA Systems Through Distributed Team Cooperation

Abstract: We develop resource and service management techniques to support secondary users (SUs) with QoS requirements in large-scale distributed dynamic spectrum access (DSA) systems. The proposed techniques empower SUs' to seek and exploit spectrum opportunities dynamically and effectively, thereby maximizing the SUs' long-term received service satisfaction levels. Our techniques are efficient in terms of optimality, scalability, distributivity, and fairness. First, they enable SUs to achieve high service satisfaction levels by quickly locating and accessing available spectrum opportunities. Second, they are scalable by performing well in systems with small as well as large numbers of SUs. Third, they can be implemented in a decentralized manner by relying on local information only. Finally, they ensure fairness among SUs by allowing them to receive equal amounts of service.

A Novel P2P VoD Streaming Technique Integrating Localization and Congestion Awareness Strategies

Abstract: The concept of the "future Internet" has evolved amongst researchers recently to relieve the tremendous pressure on the current Internet infrastructure to support the heterogeneous networking technologies, mobile devices, increased population of users, and also the high user requirements for real-time services and applications. Peer-to-Peer (P2P) Video on Demand (VoD) streaming technologies are expected to be a key technology in the future Internet. Because the existing P2P streaming techniques are attributed to a number of shortcomings, P2P VoD schemes need to be adequately redesigned for the future Internet. In this paper, we propose a scheme to effectively provide VoD by using P2P-based mesh overlay networks that may be suitable for the future Internet. Our scheme selects the most appropriate peers by exploiting domain-based localization and congestion awareness strategies. Through simulations, our proposed scheme is demonstrated to have scalability and capability of reducing the startup delay and total link cost, while maintaining high playback rate. The results are encouraging and show the importance of redesigning P2P VoD services in future Internet.

EM-MAC: An energy-aware multi-channel MAC protocol for multi-hop wireless networks

Abstract: We propose an energy-aware MAC protocol, referred to as EM-MAC, for multi-hop wireless networks with multi-channel access capabilities. EM-MAC relies on iMAC's efficient channel selection mechanism to resolve the medium contention on the common control channel, enabling wireless devices to select the best available data channel for data communication. Our protocol saves energy by allowing devices that have not gained access to the medium to switch to doze mode until the channel becomes idle again. Simulations results show that EM-MAC reduces energy consumption when compared with iMAC.

Optimal Pipeline Paging Load Balancing for Hierarchical Cellular Networks

Abstract: We study load balancing of paging schemes for multitier hierarchical cellular networks, in which different tiers of cells overlay each other to provide multiple coverage in cellular service areas. Each mobile terminal (MT) can be paged in any tier of a multitier hierarchical cellular network. Paging requests are balanced in different waiting queues of different tiers, and the load balancing among them is achieved probabilistically among N tiers. The studied paging schemes are the Hierarchical Pipeline Paging scheme, the Hierarchical Sequential Paging scheme, and the Hierarchical Blanket Paging scheme. We study two optimization problems using the N-tier load balancing: 1) given a paging delay constraint, to minimize the total paging cost under the constraint that the total delay is upper bounded by a predefined total delay, and 2) given a bound on the total delay, to minimize the total paging cost under a paging delay constraint.

A novel data collection scheme with Cluster-based Separate Network Coding for WSNs

Abstract: In this paper, we present a novel Cluster-based Separate Networking Coding (CSNC) scheme, as a solution to solve the problem of continuous data collection for WSNs with a mobile BS. By separately encoding a certain number of data segments in a combined data segment and doing decoding-free data replacement, CSNC not only provides efficient storage method for continuous data, but also maintains a high success ratio of data collection. The comprehensive performance evaluation has been conducted through computer simulation. It is shown that CSNC outperforms the existing PNC scheme significantly.

History based predictive routing in multi-lane delay tolerable VANETs

Abstract: In this paper, we propose a novel multi-lane model in Delay Tolerant Network (DTN). Different from traditional ad hoc network, DTN allows nodes to forward information in a store-and-carry manner so as to deal with the absence of end-to-end connectivity. Vehicles are classified into different categories according to their everyday routine, so called multi-lane. The main purpose is to decide a reliable next-hop forwarding procedure based on incomplete surrounding information. Furthermore, considering the searching interval during which nodes carry the information, we aim to explore the VANETs system performance under different network constraints like node density, velocity.

Cyber security for smart grid communications

Abstract: The smart grid provides a platform for thirdparty service providers to remotely monitor and manage energy usage for consumers. At the same time, the involvement of service providers brings a new set of security threats to the smart grid. In this article, we first identify the cyber security challenges on service provision in the smart grid. Then we present two main security issues related to service provision and provide potential solutions. The first one is to establish a secure communication procedure among the electric utility, consumers, and service providers. The second one is to provide a privacy-preserving yet accountable authentication framework among the smart grid entities without relying on any trusted third party. Finally, we suggest directions of future work on secure service provision by describing several open issues.

All-to-all throughput maximization in wireless relay networks with multiple packet reception

Abstract: Network Coding (NC) has shown the promise of significant throughput improvement to wireless networks. Meanwhile, Multiple Packet Reception (MPR) has been proved as an efficient way to combat the Multiple Access Interference (MAI) problem and to make wireless networks truly scalable. Their outstanding advantages to wireless network performance have attracted considerable research interests. In this paper, we find that the greedy use of MPR may take side effect to NC and degrade the overall network throughput for All-to-All (A2A) communication in two-way relay networks. To fully explore the potential of both MPR and NC, the transmission should be carefully scheduled. The optimal scheduling to achieve the maximum A2A throughput is then formulated as an Integer Programming (IP) problem. A heuristic transmission scheduling algorithm with low computational complexity is also proposed. Simulation results show that our heuristic algorithm performs very closely to the optimal solution obtained by solving the IP problem, and achieves a significantly improved performance over the greedy scheduling that always exhausts the MPR capacity. Furthermore, a non-strict monotonic relationship between the MPR capacity and the maximum A2A throughput has been also discovered from our experimental results.

Forced Spectrum Access Termination Probability Analysis under Restricted Channel Handoff

Abstract: Most existing works on cognitive radio networks assume that cognitive (or secondary) users are capable of switching/jumping to any available channel, regardless of the frequency gap between the target and the current channels. Due to hardware limitations, cognitive users can actually jump only so far from where the operating frequency of their current channel is, given an acceptable switching delay that users are typically constrained by. This paper studies the performance of cognitive radio networks with dynamic multichannel access capability, but while considering realistic channel handoff assumptions, where cognitive users can only move/jump to their immediate neighboring channels.

Understanding the topologies of BitTorrent networks: A measurement view

Abstract: BitTorrent (BT) is one of the most popular Peer-to-Peer (P2P) network applications. Most characteristics (except the topology) of BT network have been examined extensively by measurement approaches. In this work, we deploy a measurement system to study the performance-related properties of BT topologies. We also use our measurement system to verify some previous simulation and experiment results obtained by other researchers. Different from previous results, we observe that a BT swarm has short distance, low clustering coefficient and Gaussian-like degree-frequency distribution. This indicates that a BT swarm is very close to a random network rather than a scale-free network or a small world. We observe that the diameter of a BT network at the initial stage is small even when 95% of peers use the peer exchange extension but the networks are not fully connected at the steady stages.

Unidirectional flow throughput enhancement through Physical-Layer Network Coding

Abstract: The increasing demands for high data rates necessitate the development of faster schemes of exchanging information along wireless communication links. Physical-Layer Network Coding (PNC) is a promising technique that can improve the achievable data flow rates through higher packet transmission rates, thereby increasing the overall throughput. In this paper, we study the performance of the PNC transmission technique in unidirectional linear flow networks, and compare it with that of the traditional transmission technique. We first derive the bit-error rate (BER) that the PNC transmission scheme achieves, and then using that, we evaluate the end-to-end flow throughput of unidirectional flows. Our results show that PNC has a great potential for enhancing the achievable throughput, especially under medium to high signal-to-noise ratios. We also validate the derived BER results using simulations.